The present invention relates to a router apparatus using an ATM (Asynchronous Transfer Mode) switch to make routing of packets.
As a router apparatus using the ATM switch capable of exchanging signals at a high speed in the hardware manner to make routing of IP (Internet Protocol) packets, a product group named generically as IP switch made of IPSILON NETWORKS, Inc. is known.
FIG. 8 schematically illustrates this router apparatus.
As shown in FIG. 8, the router apparatus 1000 is connected among gateway apparatuses 2000 connected to LAN and WAN which adopt the IP.
The gateway apparatus 2000 receives IP packets from the LAN and WAN to make ATM cells and sends the ATM cells to the router apparatus 1000 while designating the defaulted VP and VC. An ATM switch 1100 of the router apparatus 1000 sends to an IP switch controller 1200 the ATM cells which designate the defaulted VP and VC. The IP switch controller 1200 restores the IP packets from the received ATM cells and investigates an address of the IP packets. The IP switch controller 1200 makes ATM cells which designate the defaulted VP and VC from the IP packets again and sends the ATM cells through the ATM switch 1100 to the gateway apparatus 2000 corresponding to the investigated address. The gateway apparatus which has received the ATM cells restores the IP packets from the ATM cells and sends the IP packets to the LAN and WAN connected thereto.